Understanding Clinical Trials

At TrialSearch, our mission is to guide you through what can be a confusing process of finding a clinical trial that is a match with your needs. This starts with laying out, in straightforward terms, the basics of clinical trials.

Clinical trials are research studies requiring human participants and involving medical treatments that can affect thousands or millions of individuals. As a result, stakes are very high to get the study conclusions right. There are therefore many rules and standards for how modern clinical trials are run to maximize the chance of medical success and minimize risk to individuals’ health.

FAQs about clinical trials

What Is a Clinical Trial?

Clinical trials are carefully conducted studies that test how well a new treatment, diagnostic tool, or medical procedure works for a certain disease or condition. The U.S. Food and Drug Administration (FDA) requires clinical trials to prove new treatments are both safe and effective.1

Sometimes, doctors and researchers are interested in using a previously approved therapy for treating a different disease or condition. In this case, a clinical trial is conducted using participants with the disease or condition of interest to confirm the treatment is safe and effective in a new setting.

Clinical trials take several months to years and are highly regulated studies. The investigators running them have taken every precaution to ensure you have a safe experience. While there’s no guarantee you’ll gain any benefits when participating in a clinical trial, some people may see improvements in their disease or condition.

How Clinical Trials Work

Learning about clinical trials can seem like an overwhelming process with lots of information to take in. We’ve broken down the main concepts surrounding clinical trials with additional information so you can familiarize yourself with the important points and terms to know.

Phases of Clinical Trials

Clinical trials are divided into four phases, each with the intent of learning new information about an experimental treatment. Phase 1 trials typically use between 20 to 100 healthy volunteers to determine whether a drug is safe to use in humans. These studies also focus on understanding how the body processes and breaks down the drug, and what side effects may occur.

Phase 2 and 3 trials recruit a larger group of participants who have the disease or condition being studied to determine if the treatment is effective and to identify any side effects not seen in phase 1. Phase 4 studies follow up on treatments after they’re approved to observe their long-term effects.

Learn more about clinical trial phases.

Randomization in Clinical Trials

Clinical trials are designed to prevent bias so that the results are as accurate as possible. The gold standard of clinical trials is the double-blind placebo-controlled randomized study. This means that the participant is randomly placed in the experimental treatment or placebo (“fake drug”) group. Neither the doctor nor the participant knows which treatment they’re receiving.

Learn more about how clinical trials work.

Clinical Trials and Safety

Safety standards are set in place by the FDA and different monitoring boards to ensure participants are as safe as possible. The FDA requires an institutional review board (IRB) made up of members with scientific backgrounds and at least one community member. This board reviews clinical trial protocols and ethics to ensure the participants’ rights are protected.

Before joining a clinical trial, participants must go through the informed consent process to ensure they fully understand what will happen during the study. As a trial participant, you have the right to understand the benefits and risks and any potential side effects you may experience. You’re also allowed to refuse treatment and leave a study at any time.

Learn more about participant safety during clinical trials.

Why Are Clinical Trials Needed?

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Clinical trials are needed to help put effective new therapies on the market or bring new diagnostic tools and medical procedures to doctors’ offices and hospitals. These research studies affect not only participants but potentially thousands to millions of people who may benefit from a new treatment. Clinical trials help ensure that these new medical interventions are effective and safe to introduce to the public.

Some experimental therapies may also be directly compared to existing treatments. The rigorous testing throughout the different phases over time can help doctors and researchers better understand which drugs or other treatments are the most effective. As a result, science and medicine are continually improving to help patients live longer, healthier lives.

How Are Clinical Trials Funded?

Clinical trials are funded by a clinical trial sponsor. These sponsors are usually pharmaceutical or biotechnology companies or institutions that would like to see a treatment approved. Sponsors cover any research costs associated with a clinical trial, including the cost of the medication, any additional tests or procedures, and hospital stays. You don’t pay anything to participate in a clinical trial.

Are Clinical Trials Different from Research Studies?

Research studies are performed to learn new information about how people function, behave, and learn.2 Clinical trials are a specific type of research study, falling under the umbrella of clinical research. This term refers to all research involving people with the intent to advance medicine.

There are two main types of clinical studies — interventional studies (clinical trials) and observational studies. Learn more about the different types of clinical trials.

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